Method of making contact bodies

ABSTRACT

A method of connecting contact sheets to form a contact body that provides for mechanically deforming at least same of both interior and edge projection-depression couplings formed in two sheets to form positive locks in a pair of sheets, and then mechanically deforming only edge projections to form positive locks between at least two pairs of sheets, thereby forming the contact body.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a division of prior U.S. patent applicationSer. No. 09/660,955, filed Sep. 13, 2000, entitled CONTACT BODIES ANDMETHOD AND APPARATUS OF MAKING SAME, the entire disclosure of which isincorporated herein by reference, which claimed priority from U.S.Provisional Patent Application No. 60/154,085, filed Sep. 15, 1999.

BACKGROUND OF THE INVENTION

[0002] The present invention relates to contact bodies, such asgas/liquid contact bodies, comprised of two or more individual contactsheets, and to a method and apparatus for connecting two or more contactsheets. More particularly, the present invention relates to a method andapparatus for connecting two or more contact sheets with at least onepositive lock between the contact sheets, and to the contact bodies somade.

[0003] Various types of apparatus and products are known in the art forproviding gas/liquid contact for several different purposes. Among suchpurposes, for example, are heat transfer, such as evaporative heatexchangers, the removal of pollutants from a gas (gas scrubbing), use intrickle filters (a type of biological filter), artificial reefs, andother industrial or other types of uses. Gas/liquid contact bodies aregenerally designed to promote the intimate mixture of and heat exchangebetween two fluid streams. The fluid streams can be concurrent-flowing,cross-flowing, or counter-flowing streams. The intimate mixture of twofluid streams, air and water for example, or other gases and liquids, isaccomplished by providing a series of corrugated contact sheets incontact with each other such that the crests and valleys of thecorrugations form channels or passageways. The contact body can bepositioned so that the channels are oriented in a vertical manner andthe water is allowed to trickle down the walls of each channel while agas, typically air, flows through the contact body simultaneously,thereby cooling the water. As mentioned above, the air can flowconcurrently with the water, cross-currently (i.e., horizontally in thecase of vertically disposed channels), or counter-currently. Air flowmay be improved by the use of a blower or a fan.

[0004] Many variations to the design of contact sheets used to form thecontact bodies have been described. For example, U.S. Pat. Nos.4,668,443 and 5,217,788, the entire contents of which are hereinincorporated by reference, describe various shapes and forms of contactsheets. Efforts have been directed to enhancing the wettability of thesheets, or increasing the surface area of the contact body, or reducingthe impedance to air flow, while enhancing or at least maintaining thegas and liquid contact efficiency. Variations have been made in aneffort to reduce the cost of such contact bodies, or to makeconstruction easier.

[0005] At any rate, all contact bodies comprise a plurality of contactsheets in contact with, and preferably fastened to, one another in somemanner. Most often an adhesive is used to fix one sheet to another atthe intersecting points of contact. Heat-welding is another commontechnique used in connecting the sheets. However, a problem withconventional methods of connecting contact sheets is the lack ofdurability. Adhesives and spot welds can wear and deteriorate to a pointwhere the strength of the connection is such that relatively slightforces can separate the sheets. Such a separation can be a seriousproblem to the structural integrity of a contact body. Other problemsassociated with adhesives and welding methods of connection are highcost, low speed and low productivity. The application of an adhesive atall points of contact between two adjacent contact sheets, and/or thefusing together of two sheets, is time consuming and uses a large amountof adhesive and/or energy.

[0006] Potential solutions to these problems have been proposed but havenot adequately dealt with the problems. For example, U.S. Pat. No.3,281,307, the entire contents of which are herein incorporated byreference, discloses the use of “cup-like” depressions and correspondingprojections for the purpose of situating adjacent contact sheets.However, U.S. Pat. No. 3,281,307 does not disclose or suggest that anypositive lock is provided by such projections and depressions. Furtherconnecting means, such as heat sealing, adhesives, screws, bolts andpreferably welding, are still required to join the adjacent sheetstogether. U.S. Pat. No. 5,413,872, the entire contents of which areherein incorporated by reference, describes the use of pressurefasteners. However, such a mechanism of connecting contact sheets maystill be susceptible to inadvertent separation since the amount of forcerequired to separate is equal to, or at least not significantly greaterthan, the force needed to join the pressure fasteners.

[0007] Thus, there exists a need in the art for a method of connectingcontact sheets in which the resulting connection is strong, durable,economical and substantially inseparable. The present inventionsatisfies this need.

BRIEF SUMMARY OF THE INVENTION

[0008] The present invention relates to a method of connecting contactsheets to form a contact body, comprising:

[0009] (a) providing at least a first and second pair of corrugatedcontact sheets having crests and valleys, the crests having peaksurfaces and the valleys having trough surfaces, each contact sheethaving opposing surfaces and a plurality of projections extendingoutward from one surface and located on the peak surfaces of the crestsand the trough surfaces of the valleys, the projections extending in thesame direction from the one surface of each contact sheet, wherein eachprojection defines a depression on the opposite surface of the contactsheet, some of the plurality of projections being edge projections oneach peak surface and each trough surface adjacent side edges of eachsheet, and the rest of the plurality of projections being interiorprojections on each peak surface and each trough surface in the interiorof the sheet away from the side edges;

[0010] (b) positioning the projections of one of the contact sheetswithin mating depressions of an adjacent contact sheet, thereby formingprojection-depression couplings, the edge projections and the interiorprojections of the two contact sheets of each of the first and secondpair forming projection-depression couplings with correspondingprojections of the adjacent sheet of the pair; and

[0011] (c) deforming at least some of the projection-depressioncouplings comprised of the edge projections and the interior projectionsto form positive locks in the form of flattened interlocked rivetsbetween at least some of the contact sheet projection-depressioncouplings of each pair; and

[0012] (d) deforming at least some of only the edge projections of thefirst pair of contact sheets that form projection-depression couplingswith the edge projections of the second pair of contact sheets to formpositive locks in the form of flattened interlocking rivets between thefirst and second pairs of contact sheets.

[0013] As used herein, the term “positive lock” refers to a connectionbetween two contact sheets which is formed by the deformation of aprojection-depression coupling, wherein the connection cannot beseparated without the application of a force sufficient to destroy thecoupling or adversely deform one or both of the contact sheets.

[0014] The method of the present invention provides strong and durableconnections between contact sheets which form a contact body.Furthermore, a contact body constructed in accordance with the presentinvention can be assembled quickly, easily, and without additionaladhesives or welding equipment.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0015] The foregoing summary, as well as the following detaileddescription of preferred embodiments of the invention, will be betterunderstood when read in conjunction with the appended drawings. For thepurpose of illustrating the invention, there are shown in the drawingsembodiments that are presently preferred. It should be understood,however, that the invention is not limited to the precise arrangementsand instrumentalities shown. In the drawings:

[0016]FIG. 1 is a top isometric view of a first contact sheet inaccordance with a particular embodiment of the present invention.

[0017]FIG. 2 is a top isometric view of another contact sheet inaccordance with a particular embodiment of the present invention havingcorrugations running generally transverse to the direction ofcorrugations of the contact sheet of FIG. 1.

[0018]FIG. 3 is a top isometric view of two contact sheets where thecontact sheet of FIG. 1 is overlapping the contact sheet of FIG. 2 priorto formation as a contact body by formation of a positive lock bydeforming the projection-depression couplings formed when theprojections located on the crests of the bottom sheet are located withinthe depressions in the valleys of the top sheet.

[0019]FIG. 4 is an enlarged view of a portion of a side edge of thecontact sheets of FIG. 3 after formation of the sheets into a contactbody, illustrating a positive lock created by the deformation of aprojection-depression coupling.

[0020]FIG. 5 is an isometric view of a contact body in accordance with aparticular embodiment of the present invention made from several contactsheets.

[0021]FIG. 6 is an isometric view of a pair of contact sheets positionedfor feeding through a crimping device schematically illustrated inaccordance with a particular preferred embodiment of the presentinvention.

[0022]FIG. 7 is an enlarged isometric view of the area of a positivelock formation using the crimping device of FIG. 6.

[0023]FIG. 8 is an enlarged isometric view of another crimping device inaccordance with a particular preferred embodiment of the presentinvention, showing the crimping device in an open position.

[0024]FIG. 9 is an enlarged isometric view of the crimping device shownin FIG. 8 in a closed position.

[0025]FIG. 10 is a cross-sectional view of a positive lock formed bydeforming a projection-depression coupling of two contact sheets inaccordance with a particular embodiment of the present invention.

[0026]FIG. 11 is an isometric view of one embodiment of an apparatusused to make a contact body in accordance with a particular embodimentof the present invention, where the apparatus is readily transportableto a field location.

[0027]FIG. 12 is an isometric view of a preliminary alignment station inaccordance with a particular preferred embodiment of the presentinvention, forming a component of the apparatus shown in FIG. 11.

[0028]FIG. 13 is an isometric view of a manually actuated crimpingdevice in accordance with a particular preferred embodiment of thepresent invention for use with the apparatus illustrated in FIGS. 11 and12.

[0029]FIG. 14 is an isometric view of a crimping device in accordancewith another particular preferred embodiment of the present invention,having portions of its housing removed for ease of illustration, of atype useful in the apparatus shown in FIG. 11.

[0030]FIG. 15 is a rear isometric view of an edge crimping device inaccordance with another preferred embodiment of the present invention,also having portions of its housing removed for ease of illustration,that is well suited for use in the apparatus shown in FIG. 11.

[0031]FIG. 16 is a left side isometric view of another embodiment of anapparatus for crimping together interlocked portions of at least twosheets of deformable sheet material in accordance with a particularpreferred embodiment of the present invention, wherein the apparatus issuitable for a higher production, more permanent factory installationthan the apparatus illustrated in FIG. 11.

[0032]FIG. 17 is a left-side isometric view of an alignment andpre-assembly apparatus in accordance with a particular embodiment of thepresent invention, having portions of its housing removed for ease ofillustration, used to pick and place sheet material prior to a crimpingoperation using an apparatus such as that illustrated in FIG. 16.

[0033]FIG. 18 is a left-side isometric view of another, motorizedcrimping device in accordance with a particular preferred embodiment ofthe present invention, having portions of its housing removed for easeof illustration, suitable for use in the apparatus of FIG. 16.

[0034]FIG. 19 is a right-side isometric view of the crimping deviceillustrated in FIG. 18.

[0035]FIG. 20 is an isometric view from the right front comer of anotheredge crimping device in accordance with a particular preferredembodiment of the present invention, having portions of its housingremoved for ease of illustration, useful in the apparatus of FIG. 16.

DETAILED DESCRIPTION OF THE INVENTION

[0036] Certain terminology is used in the following description forconvenience only and is not limiting. The words “lower,” “upper,”“bottom,” “top,” “front,” “back,” “left,” and “right” designatedirections in the drawings to which reference is made, but are notlimiting with respect to the orientation in which the contact body orcontact sheets or apparatus used in making the contact body are orientedin use or in the manufacturing process. The terminology includes thewords specifically mentioned above, derivatives thereof and words ofsimilar import.

[0037] Furthermore, as used herein, the article “a” or a singularcomponent includes the plural or more than one component, unlessspecifically and explicitly restricted to the singular or a singlecomponent.

[0038] Contact sheets that can be used in accordance with the presentinvention can be of any type, so long as at least two of the contactsheets have a projection extending out from one surface of the sheet,each projection defining a corresponding depression on the oppositesurface of the sheet.

[0039] The sheets may have a corrugated form wherein each sheet hascrests and valleys. The corrugations can be shaped, for example, suchthat the crests and valleys are flattened, rounded, or concave(including recesses, indentations or scalloped areas along portions ofor along the entire length of the crests and valleys). The corrugationscan be in the form of a sinusoidal wave. The number of corrugations andspecific cross-sectional shape and dimensions of each corrugation canvary widely and are not critical to the present invention. Preferably,the crests and valleys of each contact sheet have at least one portionor surface area at the peak of the crest or trough of the valley, whichis substantially parallel to the plane of the contact sheet. A preferredtype of contact sheet is that disclosed in U.S. Pat. No. 5,217,788, thedisclosure of which is hereby incorporated herein by reference, andwhich is assigned to the assignee of the present invention.

[0040] Contact sheets for use in the present invention can be made froma variety of mechanically deformable materials. The material must becapable of being mechanically deformable, such that upon a crimping,crushing or other type of mechanical deformation, the deformed materialretains its deformed shape. Thus, materials such as natural or syntheticrubber that are elastomeric and resist deformation would not be suitablematerials.

[0041] Sheet metals, thermoplastics, and composite materials composed offibers impregnated with thermoplastic materials can all be used to formthe contact sheets for use in the present invention. Sheet metals suchas galvanized steel, stainless steel, aluminum and copper can be formedinto contact sheets for use in the present invention. Thermoplasticmaterials which can be used in the present invention are, for example,polyvinyl chlorides (plasticized or unplasticized), polystyrenes,acetals, nylons, acrylonitrile-butadiene-styrene (ABS),styrene-acrylonitrile (SAN), polyphenylene oxides, polycarbonates,polyether sulfones, polyaryl sulfones, polyethylene, polystyrene,terephthalates, polyetherketones, polypropylenes, polysilicones,polyphenylene sulfides, polyionomers, polyepoxides, polyvinylidenehalides, and derivatives and/or mixtures thereof. The particularmaterial used is dependent upon the desired end use and the applicationconditions associated with that use, as is well known in the art. Forexample, in relatively low temperature cooling tower applications, apolyvinylchloride resin having little or no plasticizer is preferred.Presently it is preferred that a synthetic polymer, such aspolyvinylchloride, polypropylene, ABS, or polystyrene, be used to formthe contact sheets.

[0042] Contact sheets useful in accordance with the present inventioncan be manufactured by any conventional technique applicable to thematerial from which the contact sheet is to be made. For example, thesheets may be formed by conventional prior art processes, such asthermoforming, pressure forming, vacuum forming, molding, hot stamping,extrusion, injection molding, or the like. Thermoforming is preferred.

[0043] Each contact sheet for use in the present invention must have atleast one projection, and preferably a plurality of projections,extending outward from one surface of the contact sheet. It is generallypreferred that the projections extend out perpendicularly from the planeof the contact sheet, although projections extending at an angle otherthan 90□ from the contact sheet plane can be used in the presentinvention. The projection, or projections, can be located anywhere onthe sheet. Preferably, each contact sheet is corrugated and there is aplurality of the projections located on a crest or valley of the sheet.Most preferably, the projections are located on portions of the crestsand valleys that are substantially parallel to the plane of the contactsheet, as best shown in FIGS. 1-4.

[0044] The exact shape and size of projections in accordance with thepresent invention are unimportant. The projections are preferably in theshape of a truncated cone, however, the projections may be of any shapewhatsoever, including but not limited to, rounded cones, pyramids withthree or four triangular or truncated triangular side walls, orprojections with a cross-sectional shape of octagons, squares, etc. Itis not essential, but preferred, that the shape of the projections andany corresponding depressions be complementary, but the projection mustbe capable of fitting within the corresponding depression. Thus, forexample, a properly sized truncated pyramidal projection could fitwithin a truncated conical depression, or vice versa. By having theshapes of the projections and depressions complementary, however, betternesting of the contact sheets can be achieved before they are assembled.This helps reduce the space and the cost of packaging, shipping andstorage. Truncated cones or rounded cones are preferred due to thestrength of the joint created. Furthermore, truncated cones provide aparticularly preferred configuration with respect to packaging (nestingmultiple contact sheets together prior to assembling the sheets intocontact bodies), formability and strength.

[0045] In a particularly preferred embodiment in accordance with thepresent invention and as best shown in FIGS. 1-4, the contact sheets arecorrugated such that the crests and valleys have flat portionssubstantially parallel to the plane of the contact sheet. Also, as bestshown in FIGS. 1-4, there are a number of projections, preferably evenlyspaced along each crest and valley, extending outward from one surfaceof the contact sheet in a direction perpendicular to the surface of thecontact sheet. The illustrated projections are in the shape of atruncated cone.

[0046] The invention will now be described in detail with reference tothe drawings, wherein like numerals indicate like elements throughoutthe several views.

[0047]FIG. 1 illustrates one preferred embodiment of a contact sheet 10.Contact sheet 10 has a plurality of projections 12 and 14 extendingoutward from the surface shown as the upper surface of the contactsheet. The projections could extend downward, if desired. Theprojections, which define corresponding depressions on the oppositesurface of the contact sheet 10, are located on the crests 16 andvalleys 18 of the sheet. The crests and valleys form a corrugatedcontact sheet. Preferably, the projections are located on the peaksurfaces of the crests and the trough surfaces of the valleys that aresubstantially parallel to the plane of the contact sheet. Alsopreferably, the projections located on the peak surfaces are alignedlongitudinally with the projections located on the trough surfaces. Someof the projections are designated as edge projections 12, due to theirlocation adjacent the side edges of each sheet. The remainingprojections are designated interior projections 14, due to theirlocation in the interior of the sheet away from the side edges.Preferably, for strength and structural integrity, there are a number ofprojections on each of the peaks of the crests 16 and on each of thetroughs of the valleys 18. Likewise, for purposes of structuralintegrity and otherwise as explained in above referenced U.S. Pat. No.5,217,788, the crests and valleys may include indented or recessedportions 20, if desired.

[0048]FIG. 2 illustrates another contact sheet 22 that is similar instructure to the contact sheet 10 illustrated in FIG. 1, except that thecontact sheet 22 has corrugations formed by the crests 28 and valleys 30that cross the corrugations formed by the crests 16 and valleys 18 ofthe contact sheet 10 when the sheets 10 and 22 are joined together. Asdescribed above with respect to contact sheet 10, contact sheet 22 may,for purposes of structural integrity and otherwise as explained inabove-referenced U.S. Pat. No. 5,217,788, the crests and valleys mayinclude indented or recessed portions 32, if desired. The corrugationsof either sheet 10 or 22 are formed at any desired angle with respect tothe side edges of the contact sheets, depending on the particularequipment, environment and purpose for which the contact bodies madefrom the contact sheets are used. The corrugations of either contactsheet 10 or 22 can be of any desired shape or dimensions. Further, thecorrugations of either contact sheet need not have the same shape anddimensions or even be present throughout the entire area or surface ofthe contact sheets. The contact sheets 10 may nest one on top of theother, with the corrugations going in the same direction, for bettereconomy of packaging, shipment and storage. Likewise, the contact sheets22 may nest one on top of the other, with the corrugations going in thesame direction, for better economy of packaging, shipment and storage.

[0049] The contact sheet 22 includes a plurality of edge projections 24and a plurality of interior projections 26. The edge projections on thepeaks of the crests 28 and the troughs of the valleys 30 are insubstantial longitudinal alignment, and the interior projections 26 onthe peaks and troughs are also in substantial longitudinal alignment, asillustrated in FIG. 2 and explained above with respect to the contactsheet 10 illustrated in FIG. 1.

[0050]FIG. 3 illustrates a contact sheet 10 positioned adjacent to (ontop of) another contact sheet 22, in preparation to form a contact bodyof at least two contact sheets. The two contact sheets 10 and 22 arepositioned such that those of the projections 24, 26 (best seen in FIG.10) which are located on the crests 28 of the contact sheet 22 arelocated within the depressions defined by the opposite surfaces of thoseof the projections 12 and 14 which are located on the valleys 18 of thecontact sheet 10. Once contact sheets 10 and 22 are positioned in such amanner, the projections on the crests of the contact sheet 22 locatedwithin the depressions defined by projections on the valleys of thecontact sheet 10 form a plurality of projection-depression couplings 34.Additionally, when positioned as shown in FIG. 3, the two contact sheets10 and 22 define a plurality of channels between the sheets defined bythe spaced crests 16 of the contact sheet 10 and the valleys 30 of thecontact sheet 22.

[0051]FIGS. 4 and 10 show an enlarged view of a portion of a side edgeand a cross-sectional view, respectively, of particular embodiments ofthe present invention wherein one of the projection-depression couplingshas been deformed, namely, flattened, between a pair of platens, orsimilar crimping device, to form a positive lock 36. It should beunderstood that no particular or specific device need be used increating a positive lock between the projection and the depression of aprojection-depression coupling. Particularly preferred devices and/ormechanisms for creating a positive lock between the projection and thedepression of a projection-depression coupling are described below.

[0052]FIGS. 4 and 10 show the projection-depression coupling 34 shown inFIG. 3 after the positive lock 36 has been formed. In the embodiment ofthe present invention best shown in FIGS. 4 and 10, the positive lock 36is comprised of a flattened or crushed projection-depression coupling34. It should be understood that a positive lock in accordance with thepresent invention can be formed in several ways, such as, for example,as above by the deformation of the projection-depression coupling in adirection perpendicular to the plane of the contact sheets, by squeezingthe projection-depression coupling together in a direction parallel tothe plane of the contact sheets, by bending the projection-depressioncoupling to one side or the other, by twisting the projection-depressioncoupling, or by any other force which locks the projection of onecontact sheet within the depression of the adjacent contact sheet. It ispreferred that the positive lock be formed by flattening theprojection-depression coupling substantially in a directionperpendicular to the plane of the contact sheet.

[0053] The positive lock 36 maintains a connection between the contactsheets 10 and 22. Unlike a friction fitting, the positive lock 36connects the two contact sheets 10 and 22 in such a manner that pullingthem apart in a direction opposite to each other normally cannotseparate the sheets. It should be understood, of course, that excessiveforce, that is a force well in excess of any separative forceencountered in most applications of contact bodies, could possiblyseparate the contact sheets, but not without destruction of the positivelock(s) and/or the adverse deformation of the contact sheets themselves.Such force is usually not accidentally or inadvertently applied. Thus,once a positive lock in accordance with the present invention is formed,the contact body is assured of structural integrity to the extent thatindividual contact sheets will not separate from one another in theirusual and intended various uses and environments.

[0054]FIG. 5 shows a contact body 38 in accordance with the presentinvention. The contact body 38 is comprised of several contact sheets inaccordance with the present invention. The contact sheets are positionedadjacent to each other such that the projections of one sheet are withinthe depressions of another sheet, thereby forming projection-depressioncouplings. Several couplings are then crushed to form positive locks 36such that they are substantially flat.

[0055] In a particularly preferred embodiment of the present invention,two contact sheets in accordance with the present invention arepositioned adjacent to each other such that the projections of one sheetare within the depressions of the adjacent sheet, thereby formingprojection-depression couplings. The pair of contact sheets is then fedthrough a crimping device that can crimp or crush at least some, andpreferably all of the projection-depression couplings to form positivelocks. While it is not required, for the sake of efficient manufactureon a commercial scale, preferably, at least two projection-depressioncouplings, and more preferably, all laterally alignedprojection-depression couplings in each two-sheet arrangement aredeformed substantially simultaneously to form the corresponding positivelocks. One crimping apparatus capable of such efficiency is crimpingdevice 40, includes crimping gears shown schematically in FIG. 6,without any housing or drive mechanism shown for the sake of a moreclear illustration. The crimping device deforms theprojection-depression couplings across the entire width of the contactsheets, thereby forming positive locks between the two contact sheets.The crimping device 40 comprises a number of pairs of upper gears 42 andopposed lower gears 44, where each pair of gears comprises an upper gearand a lower gear. The number and alignment of gears corresponds to thenumber and alignment of projection-depression couplings across the widthof the pair of adjacent contact sheets. As shown in FIG. 6, for example,there are four pairs of upper gears 42 and lower gears 44, correspondingto the four projection-depression couplings 34 across the width of thepair of contact sheets. It should be understood that any number of pairsof gears could be used to correspond to the number ofprojection-depression couplings along a given width, and preferably, theentire width, of a pair of contact sheets.

[0056] Each of the upper crimping gears 42 and lower crimping gears 44has elongated teeth 46 protruding radially from the circumference of thecrimping gear body 48. Each of the teeth has a crimping surface 50. Asshown in FIG. 7, the elongated teeth 46 are long enough such that thecrimping surfaces 50 contact and deform the projection-depressioncouplings 34 without the teeth contacting the walls of the crests 16 and28, and valleys 18 and 30 of the contact sheets. The elongated teeth arespaced along the circumference of the gear body such that they contactsuccessive projection-depression couplings 34 on opposite surfaces ofthe pair of sheets simultaneously in area “A” as shown in FIG. 6 and inenlarged detail in FIG. 7, as the crimping gears rotate in the directionindicated by arrows B in FIG. 6. The arcuate spacing C of the tips ofthe teeth 46 corresponds to the spacing D of the projection-depressioncouplings 34. The crimping surface 50 at the tip of each elongated tooth46 is preferably flat and smooth, although other surface configurations,such as convex, concave, ridged, etc. can be used.

[0057] After pairs of contact sheets have been connected by formingpositive locks 36 between the projection-depression couplings 34,including those projection-depression couplings located at the edges andinterior of the contact sheets, two pairs of connected contact sheetscan be connected to each other. Any manual tool or manually-actuated orpower-actuated apparatus can be used to make positive locks by deformingas few or as many of the projection-depression couplings as desired thatare formed by interlocking one or more sheets together, or byinterlocking one sheet with a pre-joined pair or any other number ofsheets, to build up a contact body of any desired number of sheets. Allof the projection-depression couplings formed by interlocking sheets maybe deformed manually or by automated pinching, crimping or twisting jawslocated adjacent one surface of the sheet or contact body, say the uppersurface, for example. When an assembly of more than two sheets is beingmade, it may be difficult to make flattened positive locks from theprojection-depression couplings formed from the interior projections andcorresponding depressions. This is because it may be difficult to applysufficient force on such interior couplings of multiple sheets by usingapparatus that deforms the couplings by exerting force perpendicular tothe plane of the contact sheets, such as opposed tool contact surfaceson opposite surfaces of the pre-joined contact sheets.

[0058] Rather than making positive locks using all of theprojection-depression couplings (both at the interior and adjacent theside edges of all of the sheets) to lock together pairs of pre-joinedcontact sheets or by adding single contact sheets to pre-joined pairs(or more) of the contact sheets, very suitable contact bodies withexcellent structural integrity can be made by forming positive locksonly by deforming some or preferably all of the projection-depressioncouplings comprised of the edge projections 12 and 24 adjacent both sideedges of the pairs of the contact sheets. Equipment for deforming theprojection-depression couplings only adjacent the edges may takeadvantage of the ability to apply deforming compressive force onopposite surfaces of two sheets in a direction generally perpendicularto the plane of the sheets. Thus, pairs of pre-joined sheets may beattached together securely and efficiently by forming positive locksalong the side edge couplings.

[0059] Similarly, additional single sheets may be joined to an assemblyof two or more sheets one sheet at a time. However, a contact body withgreater structural integrity is formed by joining together, along theirside edges, pre-joined pairs of sheets, since the sheets of each pairmay be and preferably are joined together by making positive locks atsome and preferably all of the projection-depression couplingsthroughout the width and length of the sheets.

[0060] The projection-depression couplings along the edges of the pairsof contact sheets can be joined using a number of edge-crimping devices,such as the one shown in FIGS. 8 and 9. In FIG. 8, each edge-crimpingdevice 52, capable of forming two positive locks 36 simultaneously alongthe edge of two pairs of contact sheets, is shown in an open position.The device 52 includes an upper crimping member 54 and a lower crimpingmember 56. In the particular embodiment illustrated, the upper crimpingmember 54 is movable and the lower crimping member 56 is stationary,functioning as an anvil for the movable upper crimping member 54. Theupper crimping member 54 is mounted on a shaft 58, which can rotate inbearings within mounting blocks 58 and 60. In other designs, the movableand stationary members could be reversed. It only matters that thecrimping members are movable relative to each other. The upper crimpingmember includes two downward-facing upper crimping surfaces 62 and thelower crimping member 56 including two upward-facing lower crimpingsurfaces 64 aligned with the upper crimping surfaces 62. It should alsobe understood that an edge-crimping device 52, as shown in FIGS. 8 and9, can be adapted to include more, or fewer, upper crimping surfaces 62and aligned lower crimping surfaces 64 such that the simultaneousformation of more, or fewer, positive locks is possible. Additionally,if desired, more than two pairs of joined sheets could be joinedsimultaneously by having multiple levels of crimping devices crimp theedge couplings.

[0061]FIG. 9 shows the crimping device 52 of FIG. 8 in a closedposition. The crimping device 52 is closed by moving the upper crimpingmember 54 toward the lower crimping member using a cam arrangement, forexample. The cam arrangement includes a manually or power driven camshaft 66 connected to or unitarily formed in an offset manner with aneccentric cam 68. As shown in FIGS. 8 and 9, the eccentric cam 68 bearsagainst a follower 70 mounted on a shaft 72 that rotates in bearingswithin arms 74 that are attached to or unitarily formed with the uppercrimping member. Based on the angular position of the eccentric cam 68with respect to the follower 70, the crimping device 52 is opened orclosed. FIG. 8 shows the relationship between the cam and the followerthat opens the crimping device, while FIG. 9 shows the relationshipbetween the cam and follower that closes the crimping device, such thatthe crimping surfaces 62 and 64 apply deformation pressure to theprojection-depression couplings 34 along the edges of the contactsheets, thus forming positive locks 36.

[0062] Several pairs of contact sheets, each pair being joined bypositive locks across the width of the contact sheets, can be joinedtogether at their edges by, for example, the crimping device 52 shown inFIGS. 8 and 9, to form a contact body in accordance with the presentinvention. Contact bodies so formed are durable, economicallymanufactured, maintain strong joints by way of positive locks and alsoexhibit excellent thermal performance at least partly as a result oftheir structural integrity.

[0063] The crimping devices of FIGS. 6-9 can be driven by electric,internal combustion, pneumatic, hydraulic or other motive power sources,in addition to manual power. Appropriate gearing, camming, drive beltsand pulleys or chains and sprockets, and other associated mechanicalcomponents well known to those skilled in the motive power art couldreadily be provided with proper interconnections, as well as computercontrol systems, to properly and efficiently perform the crimpingoperations.

[0064]FIG. 10 is a cross-sectional and greatly enlarged view of apositive lock 36 in accordance with one particular embodiment of thepresent invention. FIG. 10 also shows in phantom (dashed) lines theprojection-depression coupling 34 prior to being substantially flattenedto form a positive lock 36. The positive lock 36 keeps contact sheet 10together with contact sheet 22 in a substantially inseparable manner.The term “substantially flattened” as used herein means that theprojection-depression coupling 34 has been forced toward or against thecontact sheet 10 surface to such an extent to form the positive lock 36that the sheets cannot be separated without destroying the couplingand/or adversely deforming the contact sheets. Preferably, but withoutlimitation, the coupling 34 is flattened to form the positive lock 36 tosuch an extent that some part of the outer surface of the projections 12or 14 is in contact with the contact sheet 10 surface, while maintaininga substantial amount of contact between the adjacent surfaces of thecoupled projections 14 and 24. FIG. 10 shows an idealized embodimentwhere the projection-depression coupling is completely crushed into apositive lock 36 having a form like a flattened, interlocking rivet.

[0065]FIG. 11 illustrates one form of an assembly apparatus for crimpingtogether interlocked portions of at least two sheets of deformable sheetmaterial. While the sheet material may be contact sheets as describedabove, and the apparatus is particularly well-suited to that use, theapparatus could also be used to crimp together interlocked portions ofdeformable material in which a projection is located within a depressionand retained by mechanical deformation such as crimping, regardless ofwhether the sheets have corrugations or not. Nevertheless, the apparatusis very well suited to crimp together corrugated sheets where it isdifficult to apply sufficient mechanical pressure to all of theprojection-depression couplings. Additionally, although the apparatus ofFIG. 11 could be automated and powered by electric, internal combustion,pneumatic or hydraulic motive power, the apparatus is intended primarilyfor assembling sheets such as contact sheets to form contact bodies at afield location, such as where a cooling tower or other evaporative heatexchanger is located and is being built or repaired.

[0066] The assembly apparatus of FIG. 11 includes an optional, butpreferred preliminary station 76 for aligning and initially retainingtogether a pair of sheets. The preassembled sheets are then transferred,typically by hand, over a connecting support surface, such as supporttable 81, to a first stage crimping device 77. In crimping device 77,some or all of the projection-depression couplings are deformed bycrimping to form a plurality of positive locks that provide thestructure of typically two sheets with great structural integrity. Fromthere, the assembled sheets are conveyed over another support surface,such as support table 83, to a second stage crimping device 79. Thesecond stage crimping device 79, particularly well adapted for use inthe field, deforms some or all of the edge projection-depressioncouplings, depending on the shape, number and placement of the tools, bycrimping the edge projection-depression couplings of the preformedsubassembly resulting from crimping device 77 to another or successivesheets or subassemblies added to the bottom of the first or subsequentadded subassemblies. A contact body or other structure having highstructural integrity is formed by crimping some, preferably a majority,and more preferably substantially all or all of theprojection-depression couplings formed along the edges of a plurality ofsubassemblies, where each subassembly has been assembled by deformingsome, preferably a majority, and more preferably substantially all orall of the projection-depression couplings to form the subassembly.Thus, every other layer preferably is fully joined by positive locksmade by deforming projection-depression couplings throughout its edgesand interior structure, while every remaining other layer is joinedpreferably substantially fully along its side edges. This techniquecreates a strong and durable assembly such as a contact body. As theintended product is assembled, by passing through the crimping device79, the subassemblies or completed assemblies are supported by a supportsurface, such as support table 85.

[0067] With reference to the operative components of the apparatus ofFIG. 11, an optional preliminary alignment and retention assembly unit76, illustrated in more detail in FIG. 12, is preferably used. Unit 76affords the user the ability to align sheets, preferably a pair ofsheets, such that the projections on the crests of a bottom sheet arelocated in the depressions formed in the valleys of the top sheet. Alsopreferably by using the unit 76, at least one projection-depressioncoupling is deformed to retain the alignment of the sheets. Morepreferably at least two projection-depression couplings are deformed toretain the alignment of the sheets and make further handling of thealigned sheets easier.

[0068] The preliminary alignment and retention unit 76 shown in FIG. 12includes legs 78 supporting a table having a sheet support surface 80.Sheet side edge guides 82 and an end edge guide 84 are attached to thetable at locations matching the width and length of the sheets to bealigned and pre-joined using the unit. At least one crimping device, andas shown in FIG. 12, three crimping devices 86 are located on the tableto crimp edge projection-depression couplings and retain at least twopre-joined sheets in alignment once they are aligned by hand.

[0069]FIG. 13 illustrates one type of edge crimping device 86 suitablefor use with the preliminary alignment and retention unit 76 shown inFIGS. 11 and 12. The crimping device includes a U-shaped mountingbracket 88 having upstanding flanges 89. The mounting bracket allowsready attachment to the support surface of a table, such as surface 80,by screws or other fasteners. The devices 86 are mounted on the tablearound rectangular holes in the support surface so that there is spacefor a lower crimping jaw of the device to move upwardly from a locationbelow the surface. A stop member 90 used to limit the travel of anactuator is attached to a portion of the mounting block 88 that connectsthe arms of the mounting block.

[0070] The crimping device 86 also includes a manual actuator 91 thatcan be pressed with a user's hand, a mallet or other pressing orstriking tool. If desired, the crimping device could be actuated bymotive power, such as by a motor driving a cam or gear arrangement. Theactuator 91 is unitarily formed with or attached to a Z-shaped arm 92. Alower crimping jaw 93 is unitarily formed or otherwise attached to thearm 92 at the end opposite the end including actuator 91. The tip of thecrimping jaw 93 has a crimping surface 94 that contacts theprojection-depression coupling to be deformed by crimping. The arm 92 isattached to a first shaft 95 that is rotatably mounted in bearings orbushings on the flanges 89 of the mounting block 88. A driving gear 96with its unitarily formed hub 97 is also attached to the shaft 95. Anupper crimping jaw 98 including a crimping surface 100, along with adriven gear 102 with its unitarily formed hub 104 are attached to asecond shaft 105 rotatably mounted in bearings or bushings on theflanges 89 of the mounting block 88. A tensioning coil spring, not shownfor the sake of better illustration, is attached at its opposite ends toa spring pin 106 attached to a flange 89 of the mounting block and to aspring pin 108 attached to the hub 97 of the driving gear 96. The springallows the crimping device to be in a normally open condition asillustrated in FIG. 13 until the crimping device is actuated.

[0071] The crimping device 86 operates by the user pushing down on theactuator 91. This action causes the lower crimping jaw 93 to moveupwardly as the Z-shaped arm 92 rotates around the shaft 95. Therotation of the shaft 95 causes the gear 96 to drive the gear 102, whichin turn causes the upper crimping jaw 98 to move downwardly as shaft 105rotates with the gear 102. As the lower and upper crimping jaws 93 and98 move toward each other, their respective crimping surfaces 94 and 100approach each other and deform by crimping any projection-depressioncoupling that is aligned between them. When the force pushing down onthe actuator 91 is released, the spring returns the crimping device tothe open position.

[0072]FIG. 14 illustrates one presently preferred embodiment of acrimping device 77 useful particularly for field installations. Thecrimping device 77 includes a housing 110, from which a side panel and aportion of a front panel have been removed for the sake of a more clearillustration. If desired, particularly to assure continued alignment andpositive operation, windows 112 of polycarbonate, polyacrylate or otherdurable, transparent material can be formed in one or more of thesidewalls and top of the housing. A support surface 114 supports a pairof sheets that preferably have been prealigned and initially secured inthe optional preassembly station 76. The direction of travel of thesheets through device 77 is indicated by direction arrow E. Side edgeguide rails 116 adjusted to the proper width of the sheets beingassembled are attached to the support surface 114. Upper surface guidemembers 118 are attached to the housing to retain the proper alignmentof the pair of sheets passing though the device 77 by limiting the uppermovement of the sheets in the device.

[0073] The crimping device 77 includes a crank 120 having a handle 122attached to one end. The other end of the crank 120 is attached to ashaft 124. If desired, the crank and handle could be attached to theopposite side of the crimping device or another handle and crank couldbe attached to the opposite side, such that the crimping device could beoperated from either side of the device. While the crank and handle makefor easy manual operation of the crimping device, the crimping device isreadily adaptable for actuation by motive power, such as by a motordriven sprocket and chain, belt and pulley or shaft and gear drivechains. Also mounted on the shaft 124 are a number of upper crimpinggears 42 of the type shown and described with respect to FIGS. 6 and 7.The number of crimping gears should match the number of lateral rows ofprojection-depression couplings present across the sheet pair. There arefour crimping gears used in the exemplary crimping device 77, consistentwith the number of rows of such couplings in the exemplary contactsheets. The crimping gears are aligned with each row ofprojection-depression couplings. A driving gear 126 is also mounted onthe shaft 124. The teeth of the driving gear 126 mesh with the teeth ona driven gear 128 that is mounted on a shaft 130. A number of lowercrimping gears 44 corresponding to the number of upper crimping gears 42are mounted on the shaft 130 and aligned with the upper crimping gears42.

[0074] To operate the crimping device 77, a pair of sheets is insertedinto the upstream end of the device under the upper surface guidemembers 118 until the leading edge of the sheets contact the teeth 44 ofthe upper and lower crimping gears, at which time the sheets may bepushed farther into the device so that the crimping surfaces justcontact the first aligned series of projection-depression couplings. Theuser then turns the handle 122 to rotate the gears 126 and 128 in thedirection indicated by arrows F. Turning the handle causes the upper andlower crimping gears to rotate. The teeth 46 pull the pair of sheetsthrough the crimping device as the crimping surfaces 50 deform theprojection-depression couplings passing between them to form positivelocks. Preferably, all of the couplings throughout the length and widthof the sheets are deformed by crimping to form the positive locks,although if desired, less than all of the couplings could be sodeformed.

[0075] As the joined pair of sheets exits the crimping device 77, theyare deposited onto a support table 83 prior to entering the next stationcomprising an edge crimping device 79 that is used to attach pairs ofpreassembled sheets together to form a contact body of any desirednumber of sheets.

[0076] Details of the crimping device 79 are shown in FIG. 15, a rearisometric view, where the device is shown without its housing for thesake of a more clear illustration. The crimping device 79 includes asupport structure 132 that supports a contact body support surface 134by legs 136. An optional contact body height guide bar 138 is providedto make it easy to determine when the desired number of pairs of contactsheets are joined or the desired number of individual sheets are joinedto the previously assembled stack of contact sheets, to make the contactbody. Two pairs of gearbox support walls 140 are attached to the supportstructure 132 to support gearboxes 142 on opposite sides of the contactbody. The gearboxes contain appropriate shafts, gears and joints todrive upper crimping gears 144 and lower crimping gears 146. Thecrimping gears have teeth 146 ending in beveled crimping surfaces 150.The upper crimping gears 144 are oriented with respect to the lowercrimping gears 146 and the side edges of the contact sheets being formedinto contact bodies in a manner such that the projection-depressioncouplings along each edge are deformed by crimping between the crimpingsurfaces 150 of each pair of upper and lower crimping gears as thecontact sheets move through the crimping device 79.

[0077] The crimping device 79 also includes a crank 152 having a handle154 attached to one end. The other end of the crank 152 is attached to ashaft 156. If desired, the crank and handle could be attached to theopposite side of the crimping device or another handle and crank couldbe attached to the opposite side, such that the crimping device could beoperated from either side of the device. While the crank and handle makefor easy manual operation of the crimping device, the crimping device isreadily adaptable for actuation by motive power, such as by a motordriven sprocket and chain, belt and pulley or shaft and gear drivechains. The other end of the shaft 156 is attached to a universal joint,which is hidden by a gearbox support wall 140 shown on the right-handside of FIG. 15. That universal joint is also attached to a first shaft(not shown) entering the gearbox 142 shown on the right-hand side ofFIG. 15. Mounted on that first shaft in the gearbox is a driving gearthat drives another gear mounted in the gearbox on a second shaft at aright angle to the first shaft. Also mounted on the first shaft is theupper crimping gear 144 shown on the right-hand side of FIG. 15. Thelower crimping gear 146 shown on the right-hand side of FIG. 15 ismounted on a portion of the second shaft extending from the gearbox. Adepending end of the second shaft is attached to a universal joint 158that in turn is attached to one end of a shaft 160. The other end of theshaft 160 is attached to another universal joint 162. The universaljoint 162 is attached to an end of a shaft on which the lower crimpinggear 146 shown on the left-hand side of FIG. 15 is mounted. The otherend of that shaft extends into the gear box 142 shown on the left-handside of FIG. 15, which has a similar gear and shaft arrangement as thegear box 142 shown on the right-hand side of FIG. 15.

[0078] The gearbox and other drive chain arrangements are such that therotation of the handle 154 causes the upper and lower crimping gears torotate in opposite directions to move the contact sheets and partiallyor fully assembled contact body made from them in a directioncorresponding to a direction perpendicular to and into the plane of thedrawing sheet of FIG. 15. As the crimping gears rotate, the beveledcrimping surfaces 150 deform by crimping between them theprojection-depression couplings to form positive locks preferably allalong each side edge of the contact sheets. When one pass is made thoughthe crimping device 79 to attach one pair of contact sheets to anotherpair or to an additional single sheet, the assembly so made is supportedby the support table 85. If successive pairs or single sheets are to beadded to the assembly previously passing though the crimping device 79,each successive pair of pre-joined sheets or each additional singlesheet is placed on the support table 83 and the previously assembledsheets or contact body is placed on top of the pair or single sheet.This assembly is then run again through the crimping device 79 to attachthe lower pair of sheets or single sheet to the previously joinedassembly. The process is repeated until a contact body or other assemblyof the desired number of sheets is completed.

[0079] The apparatus illustrated in FIGS. 11-15 is well suited forcrimping at least two projection-depression couplings togethersimultaneously. It is most preferred that the at least two substantiallysimultaneous crimping operations being performed using each of thecrimping devices 77 and 79 form positive locks along both side edges ofthe sheets being assembled together. However, if desired, the crimpingdevices can have crimping tools along only one side edge of the sheets.This would usually result in running the sheets though the crimpingdevices a second time so that positive locks could be formed at leastadjacent the other side edges of the sheets. While this would requireadditional labor, such an arrangement may be justified by lower cost ofsuch equipment, particularly where smaller assembly jobs are involved.

[0080]FIG. 16 illustrates another embodiment of an apparatus forcrimping together interlocked portions of at least two sheets ofdeformable sheet material in accordance with a particular preferredembodiment of the present invention, wherein the apparatus is suitablefor a higher production, more permanent factory installation than theapparatus illustrated in FIG. 11. This apparatus comprises an optionalbut preferred preliminary station 164 to pick and place and align a pairof sheets together before they are moved to the first crimping station.The apparatus also comprises a first crimping device 166 that formspositive locks between the pair of sheets by deforming some, preferablya majority, and most preferably substantially all or all of theprojection-depression couplings present in the sheets. The apparatusfurther comprises another crimping device 168 that crimps theprojection-depression couplings along the side edges of the sheets. Thisapparatus is intended to be operated using motive power, rather thanmanually, but the apparatus may be outfitted for manual operation ifdesired. The apparatus of FIG. 16 is preferably located near thelocation where the sheets are made by thermoforming or othermanufacturing technique. This makes the overall sheet formation andassembly operation more efficient, in that the sheets being formed areassembled promptly, rather than going into inventory. In at least someinstances, it may be preferred to ship the sheets to a job site forfield assembly. The apparatus shown in FIG. 16 could certainly be usedfor field assembly of the sheets, but the cost of manufacturing andshipping such apparatus may make it more economical to make the contactbodies or other assembly of sheets at or near the place where the sheetsare made and ship such assemblies to the job site.

[0081]FIG. 17 shows the optional but preferred alignment andpre-assembly apparatus 164 in accordance with a particular embodiment ofthe present invention used to pick and place sheet material prior to acrimping operation preferably using the other stations in an apparatussuch as that illustrated in FIG. 16. Portions of the housing of theapparatus 164 have been removed in FIG. 17 for better clarity ofillustration. The pick and place apparatus 164 is preferably locatednear the end of the equipment used to make the sheets to be assembledusing the apparatus shown in FIG. 16, for the reasons noted above.

[0082] The apparatus 164 includes a table with a support structure 170having legs 172. A sheet support surface 174 is divided into twoadjacent sides. A first side 176 contains one or a stack of sheets andmay be considered to be the feeding side of the sheet support surface. Asecond side 178 receives sheets from the first side 176 and may beconsidered the fed side of the sheet support surface. Side guide rails180 and 182 are attached to the sheet support surface 174, as is amiddle guide rail 184. The middle guide rail 184 acts as one side guiderail for the side edges of opposite sides of the sheets on each of thefirst and second sides 176, 178 of the sheet support surface. The otherside guide rails 180 and 182 form the guide rails for the opposite sideedges of the sheets on the first and second sides 176, 178 of the sheetsupport surface. End guide rails or stops 185 are also attached to thesheet support surface 174. The side, middle and end guide rails arelocated in positions determined on the basis of the dimensions of thesheets to be aligned and assembled using the apparatus of thisinvention.

[0083] A plurality of holes 177 are formed in both sides of the sheetsupport surface to be aligned with the placement of at least some of thedepressions formed on the opposite surface of the projections in thevalleys of the sheets to be aligned by the apparatus 164. As illustratedin FIG. 17, two rows of laterally located holes 177 are formed in eachof the sides 176 and 178 of the sheet support surface 174. The numberand location of the holes is chosen based on the number needed to alignthe sheets accurately with respect to each other on each side of thesheet support surface. Extending through each of the holes 177 is analignment pin 179 that is normally retracted when the sheets are firstplaced or slid onto the first and second sides of the sheet supportsurface 174.

[0084] Once the sheets are in approximate alignment between the sideguide rails and the end guide rail, the alignment pins 179, attached toa vertically reciprocable table (not shown) below the sheet supportsurface 174, are extended upwardly to fit within the designateddepressions of the bottom sheets to be aligned. The upward extension ispreferably accomplished by actuating a switch that controlspneumatically operated lifters (not shown) beneath the pin supporttable. The lifters are supported by two lift support members 181attached to the support structure for the apparatus 164 underneath thesupport surface and underneath the alignment pin table. Preferably, eachlift support member 181 supports a pair of lifters so that each side 176and 178 has a pair of lifters to raise the alignment pin table evenlywhen the pneumatic lifter controls are activated.

[0085] The apparatus 164 also includes an electricity supply anddistribution unit 186, a wire within a protective conduit 188 leading toa switching control unit 190 that preferably requires two-hand operationto assure that a user's hands are both needed to turn on the apparatusso that the user's hands are out of the way when the apparatus isactivated. Additionally, the apparatus comprises a pneumatic lifter 192,a suction sheet lifter head 193 connected to the pneumatic lifter 192 bysupport connection bars 194, a photocell position sensor 195, a pair ofpneumatic lateral motion devices 196, and a suction supply manifold 198that is connected to a number of suction tubes 200, each terminating inan opening at the underside of the suction sheet lifter head 193. Anadditional switch control unit 202 with appropriate electricalconnections is also provided to control airflow supplying the pneumaticpower and suction that is preferred for operating the apparatus.

[0086] Separate sources (not shown) of suction and compressed air may beprovided or, preferably, a single source (not shown) of compressed airmay be provided. Where a single source of compressed air is provided,the compressed air is routed through a conduit and any appropriatevalves to a venturi unit (not shown) having a separate outlet thatcreates a suction. A suction supply conduit (not shown) connects thesuction outlet from the venturi unit using appropriate remote controlvalves (not shown) to the suction supply manifold 198. If desired, thelifters for the alignment pin table (not shown), the lifter 192 for thesuction sheet lifter head and the lateral motion devices 196 may operateother than pneumatically, such as hydraulically, or mechanically usingracks and pinions, cams or other mechanical components with appropriatemotors operatively connected using matched drive systems such as gears,chains and sprockets or belts and pulleys, or electromagneticallyactuated devices such as solenoids. If any of these alternative drivingmeans were to be used, the source of compressed air could be eliminatedin favor of a single suction source. However, since considerableadditional equipment would have to be used for any of the alternativedriving means, resulting in additional expense for material and labor, apneumatic driving means is preferred.

[0087] Once a sheet is aligned on each of the first and second sides176, 178 of the support surface 174, the photocell position sensor 195and suction are activated using the switch control unit 202. Theoperator then activates the pneumatic lift 192 and lateral motiondevices 196 using the safety control unit 190. When all of these devicesare activated, the suction sheet lifter head moves downward toward thesheet on the first or feed side 176 controlled by the pneumatic lifter192. When the suction sheet lifter head 193 reaches the bottom of itstravel, the suction sheet lifter head 193 then picks up the sheet bysuction, and the pneumatic lifter 192 raises the suction sheet lifterhead 193 and the sheet it has lifted by suction. The photocell sensorsenses that the lifter head 193 is above a given level and sends anelectrical signal to the control circuitry causing the appropriatepneumatic valves to open, in turn allowing the pneumatic lateral motiondevices to shift the lifter head 193 and the sheet it has lifted to aposition overlying the sheet on the second or fed side 178 of thesupport surface 174. The lifter head 193 is then lowered by thepneumatic lifter 192 to place the sheet it is carrying onto the sheetaligned on the second or fed side 178. Since both sheets were previouslyproperly aligned, when the sheet is lifted and fed from the first side176 to the section side 178, it remains in alignment for proper, alignedplacement on top of the sheet in place on the second fed side 178. Thesuction through the suction sheet lifter head 193 is then interrupted sothat the fed sheet remains in alignment on top of the sheet on thesecond side 178 of the sheet support surface 174. The lifter head 193 isthen lifted upward by the pneumatic lifter 192, the photocell sensorsenses that the lifter head has been lifted and sends a signal toactivate the pneumatic control valves so that the lateral motion devices196 shift the lifter head laterally back into its original position overthe first, feed side 176, ready to begin the cycle again.

[0088] The aligned pair of sheets may then be moved in the direction ofarrow G shown in FIG. 17 to the next station for securing the pair ofsheets together by forming a plurality of positive locks by deforming aplurality of projection-depression couplings.

[0089]FIGS. 18 and 19 illustrate left-side and right-side isometricviews, respectively, of the next station in the apparatus shown in FIG.16, namely, a station 166 including a motorized crimping device 204 forcrimping projection-depression couplings formed in a pair of alignedsheets. Preferably, but optionally, the pair of sheets has been alignedpreviously using the pick and place alignment apparatus 164 describedabove with respect to FIG. 17. If the optional pick and place alignmentapparatus is not used, the station 166 becomes the first station in amotorized or automated operation for crimping together at least twosheets of deformable sheet material having a plurality ofprojection-depression couplings. The basic function and operation ofcrimping device 164 are similar to the function and operation of thecrimping device 77 used in the apparatus illustrated and described abovewith respect to FIG. 11 that was adapted primarily for field operations.

[0090] The motorized crimping device 204 is mounted on support table206. If the pick and place alignment apparatus 164 is used, thedownstream end of the second or fed side 178 of that apparatus isaligned with the upstream end of the crimping device 204 that includes asupport surface for the pair of sheets being fed into the device in adirection identified by arrow H in FIGS. 18 and 19. The crimping device204 has a housing 208 seen intact in FIG. 16, but portions of thehousing 208 have been removed in the views of FIGS. 18 and 19 for thesake of better clarity of illustration. Mounted for rotating motion inthe housing 208 is a plurality of upper crimping gears 210 and opposedlower crimping gears 212. Four of such pairs of crimping gears are usedif there are four rows of projection-depression couplings to be deformedacross the width of the pair of sheets. More or fewer crimping gears canbe added to crimp the desired number of projection-depression couplingsformed across the width of any given pair of sheets. Since thestructure, function and operation of the crimping gears that formpositive locks by crimping the projection-depression couplings have beendescribed above with respect to FIGS. 6, 7, 11 and 14, and thestructure, function and operation of the crimping gears 210 and 212 arethe same as those discussed above, that description need not be repeatedhere, but instead, is incorporated by reference.

[0091] Side edge guide rails 216 and 218, adjusted to the proper widthof the sheets being assembled, are attached to the support surface 214of the motorized crimping device 204. The station 166 also includesupper surface guide members 219, some portions of which are illustratedin FIGS. 18 and 19 as broken away for better clarity of illustration ofother components of the crimping device 204. The upper surface guidemembers 219 are attached to the housing 208 and/or to the side edgeguide rails 216 and 218 to retain the proper alignment of the pair ofsheets entering and passing though the device 266 by limiting the uppermovement of the sheets in the device.

[0092] A motor 220, such as an electric motor, a motor driven by aninternal combustion engine or a hydraulic motor, is also mounted on thesupport table 206. The motor drives a first drive chain assembly 222shown in FIG. 19. The first drive chain assembly 222 preferablycomprises any appropriate gearing; a first, driving sprocket mounted ona first shaft 223 (a driveshaft) on which is also mounted the motorgears; a first, driving chain that is driven by the driving sprocket todrive a first driven sprocket mounted on a second shaft 224; a second,driving sprocket also mounted on the second shaft; and a chain driven bythe second, driving sprocket to drive a second, driven sprocket that ismounted on a third shaft 226. The lower crimping gears are also mountedon the second shaft 224. Two alignment and feeding gears 213 are mountedon the third shaft 226. If desired more than two such gears could bemounted on the shaft 226. The alignment and feeding gears 213 have teeththat extend through slots 215 formed in the sheet support surface 214and are aligned with the depressions formed on the opposite surface ofthe bottom sheet formed by the edge projections adjacent both side edgesof the sheets being joined by the crimping device 204. The alignment andfeeding gears are spaced to register with and extend into at least twoof the depressions in a lateral row of the depressions formed in thebottom sheet passing through the crimping device 204, and are alsolocated with respect to the crimping surfaces of the upper and lowercrimping gears 210, 212 to synchronize the feeding of the sheets toassure proper crimping of the projection-depression couplings of thepair of sheets passing through the crimping device 204. Since the teethof the alignment gears are registered with and extend into at least aportion of a lateral row of the depressions formed in the bottom sheet,and since the upper sheet of the pair of sheets passing through thecrimping device 204 is aligned with the lower sheet, as the alignmentand feeding gears rotate, they pull the aligned pair of sheets throughthe crimping device in proper alignment and registration for thecrimping gears to form positive locks with the desired number, andpreferably substantially all or all of the projection-depressioncouplings of the pair of sheets.

[0093] The motor 220 also drives a second drive chain assembly 228located on the opposite side of the housing 208 with respect to thefirst drive chain assembly 222 and is shown in FIG. 18. The second drivechain assembly 228 is driven by a sprocket mounted on the second shaft224 that is driven by the motor as described above. The second drivechain 228 preferably also includes a second sprocket or gear driven bythe sprocket mounted on the second shaft 224. The second sprocket orgear drives a chain that in turn drives a third sprocket mounted on ashaft 230 on which is also mounted the upper crimping gears 210.

[0094] In view of the explanation of the operation of the first drivechain 222 and the second drive chain 228, it should be clear that themotor 220 drives not only the upper crimping gears 210 and the lowercrimping gears 212, but also the alignment and feeding gears to feed thesheet pair through the crimping device 204 in proper alignment,registration and syncronization with the crimping surfaces of thecrimping gears 210 and 212. Although the first and second drive chainassemblies have been described with respect to using sprocket and chaincomponents, other suitable drive chain assembly components could be usedinstead, such as belt and pulley or shaft and gear drive chaincomponents.

[0095] A control panel of switches 232 is electrically connected usingappropriate circuitry to an electricity supply and distribution unit 234and the motor 220 controls the operation of the motorized crimpingdevice 204. In operation, a pair of sheets is inserted into the upstreamend of the device until a lateral row of projection-depression couplingsis aligned with the alignment and feeding gears. The motor is actuatedby turning on a switch of the control panel 232. The motor drives thealignment and feeding gears to feed the pair of sheets in the directionof arrow H into the crimping device 204. The motor 220 also causes theupper and lower crimping gears to rotate. The rotating teeth of thecrimping gears pull the pair of sheets through the crimping device asthe crimping surfaces on the teeth of the crimping gears deform theprojection-depression couplings passing between them to form positivelocks. Preferably, all of the couplings throughout the length and widthof the sheets are deformed by crimping to form the positive locks,although if desired, less than all of the couplings could be sodeformed.

[0096] As the joined pair of sheets exits the crimping device 204 at thestation 166, the pair of sheets is deposited onto a support table priorto being deposited at the next station comprising a motorized andautomated edge crimping device 168 that is used to attach pairs ofpreassembled sheets together to form a contact body or any otherstructure having any desired number of assembled sheets.

[0097] The motorized and automated side edge crimping device 168 has thesame function and purpose as the manually operated edge crimping devicesshown and described with respect to FIGS. 8, 9, 13 and 15, butpreferably (although not exclusively) uses a plurality of the edgecrimping tools 52 shown and described with respect to FIGS. 8 and 9 aspart of a different crimping device or apparatus than the crimpingdevices of FIGS. 12, 13 and 15. Thus, the basic function and purpose ofthe previously described side edge crimping device 79 and those of themotorized side edge crimping device 168 are the same, namely, to deformby crimping between the edge crimping tools a sufficient number,preferably a majority and more preferably substantially all or all ofthe projection-depression couplings adjacent the edges of more than apair of sheets to form positive locks preferably all along both sideedges of the sheets and build an assembly of sheets. However, themotorized side edge crimping device 168 is considerably moresophisticated and performs the function for the same purpose in adifferent way.

[0098] The motorized crimping device 168 as shown in FIG. 20 hasportions of its housings, shown fully assembled in FIG. 16, removed forthe sake of better clarity of illustration. The device 168 includes anappropriate support structure generally designated by reference numeral236, having a framework, legs, bracing, etc., sufficient to support thedevice. A number of location and alignment members 238 are attached to avertically adjustable sheet and contact body support table 239. Thelocation and alignment members 238 have an upper surface molded toconform to the lower surface of the bottom or first sheet of an assemblyof at least three sheets, and typically more than two pairs of sheets tobe processed in the device 168. A sufficient number, such as four forexample, of members 238 are attached to and spaced along the length ofthe support table 239 to properly locate and align the sheets on thesupport table 239. The number can be determined empirically with respectto the dimensions of any given assembly of sheets being joined together.Side edge guide rails 246 also help with alignment of the sheets beingjoined together.

[0099] The device 168 also includes a sufficient number of support tabletelescoping supports 240 connected to the table framework and to thesupport table 239, and threaded height adjustment rods 242 for adjustingthe height and vertical travel of the support table 239. The top of therods 242 are connected by rotatable slip joints to the bottom of thesupport table. A motor 244 controls the height and vertical travel ofthe support table 239 by driving, through a suitable linkage formingpart of a drive chain assembly, appropriate gears, such as threaded wormgears, that turn the height adjustment rods within a housing fixedrelative to the framework of the support table, so that as the rods 242rotate in one direction, the support table 239 is raised and as the rods242 rotate in the opposite direction, the support table 239 is lowered.

[0100] A number of edge crimping tools, preferably of the type shown anddescribed as crimping tools or devices 52 with respect to FIGS. 8 and 9,are mounted to and in lateral alignment along edge crimping tool supportassemblies 249 located along each side of the device 168. With referenceto FIGS. 8 and 9, as well as to FIG. 20, the edge crimping device 168includes a common cam shaft 66 on which are mounted a plurality of theeccentric cams 68, each of which controls the opening and the closing ofthe jaws of one of the crimping tools aligned along each of the supportassemblies 248. The ends of each of the common camshafts 66 are alsoshown at the left-hand side of FIG. 20 (corresponding to the front ofthe device 168). The opposite end of each common camshaft 66 isoperatively connected to a rack and pinion assembly 250 attached to theframework of the device 168. A pneumatic driver 252 drives the rack andpinion assembly. Actuation of the pneumatic driver 252 causes relativemovement of the rack and pinion assembly, resulting in the arcuatemovement of the cam shaft 66 and the plurality of mounted eccentric camsthat control the opening and closing of the jaws of the crimping tools52. The compressed air to operate the pneumatic drivers can come fromthe same source as the source of the compressed air described above withrespect to the pick and place alignment device 164. As before, othertypes of actuators, besides pneumatic drivers, may be used to drive therack and pinion assembly to open and close the jaws of the edge crimpingtools 52. Non-limiting examples include hydraulic actuators, orelectromagnetically actuated devices such as solenoids.

[0101] To effect crimping of the projection-depression couplings alongthe side edges of two pairs of prejoined sheets, or to effect similaredge crimping involving a pair of pre-joined sheets and one or moreadditional sheets, the edge crimping tool support assemblies 248 aremoved laterally toward each other and the centerline of the apparatus168, after the pairs of sheets or at least one single sheet and a pairor many pairs of sheets have been aligned. Lateral motion devices 264,such as pneumatic actuators, move each of the support assemblies 248laterally until the jaws of the side edge crimping tools are positionedover the aligned projection-depression couplings they are intended todeform to form positive locks. Four such lateral motion devices 264, twofor each of the tool support assemblies 248, one at the front and one atthe back of the apparatus 168, are illustrated in FIG. 20, although moreor fewer could be used if desired. Non-limiting examples of other typesof actuators besides or in addition to pneumatic actuators for thelateral motion devices, include hydraulic actuators, orelectromagnetically actuated devices such as solenoids.

[0102] When one pair of sheets is joined along its side edges to anotherpair or to an additional single sheet, the assembly so made is supportedby the support table 239. If successive pairs or single sheets are to beadded to the assembly previously processed at the station 164, eachsuccessive pair of pre-joined sheets or each additional single sheet isplaced on top of the previously assembled sheets or contact body. Theentire stack is lowered by lowering the support table 239 a distanceequal to the vertical distance between the previously formed positivelocks and the next vertical level of positive locks to be formedcorresponding to the new top layer of single or pre-joined pairs ofsheets. The process is repeated until a contact body or other assemblyof the desired number of sheets is completed. Once a stack of severalsheets or pairs of sheets has been joined along the side edges, thesupport table 239 is relative low, and the assembled sheets need to beremoved from the station 168 and the cycle repeated for other assembliesof sheets.

[0103] A motor 254 is attached to the framework of the support structure236 for the motorized crimping device 164. This motor, like motor 244,is preferably an electric motor, although other types of motors can beused for either motor 244 or motor 254, including by way of non-limitingexample, internal combustion motors and hydraulic or pneumatic motors.The motor 254 through a drive chain assembly 256, preferably in the formof a belt and pulleys, drives a shaft 258 that rotates within bearings260 attached to the support structure 236 for the device 168. Alsomounted on the shaft 258 are a pair of pulleys driving conveyor belts262 that loop around similar pulleys mounted on a freely rotating shaftmounted in bearings attached to the support structure at the other endof the device 168. The motor 254 is activated at a time when the supporttable 239 is lowered to a position below the level of the top run of theconveyor belts 262, such that the bottom sheet, and therefore all sheetsstacked thereon comprising the assembled sheets, are supported by thetop run of the conveyor belts 262. The motor 254 causes the top run ofthe belts 262 to convey the stack of assembled sheets in the form of acontact body or other structure in a direction of the arrow I in FIG. 20away from the motorized edge crimping station 168 so that another stackof pairs or single sheets may be joined along their side edges at themotorized edge crimping device 168.

[0104] The apparatus 168 includes an appropriate electricity supply anddistribution unit, including control panels with the necessary switcheswith appropriate circuitry that could be made readily by a skilledelectrician. Sources of compressed air to run the pneumaticallycontrolled actuators and motors are readily available or could begenerated in situ using a compressor or the like.

[0105] To operate the apparatus 168, two pairs of pre-joined sheets or apair and one or more single sheets are fed into or placed into theapparatus 168, such that the bottom sheet is aligned over the locationand alignment members 238. When the sheets are aligned, the lateralmotion drivers 264 are actuated, causing the support assemblies 248 thatcarry the edge crimping tools 52 to move the tools into crimpingposition. When the crimping tool jaws are aligned above and below theprojection-depression couplings along the side edges to be deformed bycrimping, the pneumatic drivers 252 for the rack and pinion assemblies250 cause the proper degree of rotation of the cam shafts 66, therebysimultaneously causing the jaws of the crimping tools 52 to close andform the positive locks by deforming the edge projection-depressioncouplings aligned with the jaws. The jaws of the crimping tools are thenopened by causing the pneumatic drivers 252 to move the rack and pinionassembly to the jaws' open position.

[0106] Successive pairs of sheets or single sheets to be edge crimpedare added to the top of the stack of the pre-assembled sheets. Theheight adjustment motor 244 is activated to rotate the threaded heightadjustment rods 242 sufficiently to lower the support table 239 by anamount that allows the edge crimping tools to align with the next higherlevel of sheets to be processed as described above. The cycle isrepeated until the desired number of sheets or pairs of sheets have beenadded to and positively locked to the sheet assembly.

[0107] When the desired number of sheets are formed into the contactbody or other sheet assembly, the motor 244 is again actuated to lowerthe surface of the support table 239 below the level of the top run ofthe conveyor belt 262, such that the contact body or other sheetassembly is supported by the top run of the conveyer belt 262. The motor254 is then actuated to convey the contact body or other sheet assemblyaway from the apparatus. Once the contact body or other sheet assemblyhas been removed, motor 244 is reversed to raise the support table 239to the starting height.

[0108] If desired, the entire operation represented by any or preferablyall of the component stations or apparatus 164, 166 and 168 could beautomated and controlled by an appropriately programmed general-purposedigital computer. There are a limited number of steps that need beprogrammed, and a computer programmer of ordinary skill in the art coulddevelop an appropriate computer program based on the detailed disclosureset forth herein without undue experimentation.

[0109] It will be appreciated by those skilled in the art that changescould be made to the embodiments described above without departing fromthe broad inventive concept thereof. It is understood, therefore, thatthis invention is not limited to the particular embodiments disclosed,but it is intended to cover modifications within the spirit and scope ofthe present invention as defined by the appended claims.

What is claimed is:
 1. A method of connecting contact sheets to form acontact body, comprising: (a) providing at least a first and second pairof corrugated contact sheets having crests and valleys, the crestshaving peak surfaces and the valleys having trough surfaces, eachcontact sheet having opposing surfaces and a plurality of projectionsextending outward from one surface and located on the peak surfaces ofthe crests and the trough surfaces of the valleys, the projectionsextending in the same direction from the one surface of each contactsheet, wherein each projection defines a depression on the oppositesurface of the contact sheet, some of the plurality of projections beingedge projections on each peak surface and each trough surface adjacentside edges of each sheet, and the rest of the plurality of projectionsbeing interior projections on each peak surface and each trough surfacein the interior of the sheet away from the side edges; (b) positioningthe projections of one of the contact sheets within mating depressionsof an adjacent contact sheet, thereby forming projection-depressioncouplings, the edge projections and the interior projections of the twocontact sheets of each of the first and second pair formingprojection-depression couplings with corresponding projections of theadjacent sheet of the pair; and (c) mechanically deforming at least someof the projection-depression couplings comprised of the edge projectionsand the interior projections to form positive locks in the form offlattened interlocked rivets between at least some of the contact sheetprojection-depression couplings of each pair; and (d) mechanicallydeforming at least some of only the edge projections of the first pairof contact sheets that form projection-depression couplings with theedge projections of the second pair of contact sheets to form positivelocks in the form of flattened interlocking rivets between the first andsecond pairs of contact sheets.
 2. The method according to claim 1,wherein the projections of each contact sheet are in the shape of atruncated cone.
 3. The method according to claim 1, wherein the peaksurfaces and trough surfaces have portions that are substantiallyparallel to the plane of the contact sheet.
 4. The method according toclaim 1, wherein the plurality of projections are spaced along the peaksurfaces and the trough surfaces, the projections located on the peaksurfaces being aligned longitudinally with the projections located onthe trough surfaces.
 5. The method according to claim 1, furthercomprising mechanically deforming all of the projection-depressioncouplings of the sheets forming each of the first and second pairs toform positive locks between all of the contact sheet projections of eachof the first and second pairs, and mechanically deforming all of theedge projections of the first pair of contact sheets that formprojection-depression couplings with the edge projections of the secondpair of contact sheets to form positive locks between the first andsecond pairs of contact sheets.
 6. The method according to claim 1,wherein the contact body further comprises a plurality of pairs ofcontact sheets.
 7. The method according to claim 6, further comprisingmechanically deforming all of the projection-depression couplings ofeach pair of the contact sheets to form positive locks between all ofthe contact sheet projections of each pair, and the method furthercomprising mechanically deforming all of the edge projections of eachpair of contact sheets that form projection-depression couplings withthe edge projections of an adjacent pair of contact sheets to formpositive locks between each adjacent pair of contact sheets.